Water release transfer



May 28, 1968 K. w. J. NEALE ETAL. 3,385,748

WATER RELEASE TRANSFER Filed July l5. 1963 fggggcmr PRorEcr/vE DES/6N Z2 4 LAYER 3 LAYER. Y

ADHESIVE F'LM 525%@ 7 United States Patent O 3,385,748 WATER RELEASETRANSFER Kenneth William James Neale and David Wellings Pointon,Stoke-on-Trent, England, assignors to Johnson, Matthey & CompanyLimited, London, England, a British company Filed July 15, 1963, Ser.No. 295,054 Claims priority, application Great Britain, July 17, 1962,27,390/ 62 1 Claim. (Cl. 161-6) 'This invention relates generally toimprovements in and relating to the decoration of heat-resisting bases,that is to say, bases capable of withstanding firing at a temperature ofat least 400 C. such as glass, fused silica, or pottery, and is moreparticularly concerned with the decoration of such bases with a designor decoration in gold by mean-s of decalcomanias or transfers.

A decalcomania or transfer for use in the decoration of a heat-resistingbase usually comprises a sheet or backingor absorbent paper carrying alayer of Water-soluble gum to 'which is directly :applied either acellulose support film, which itself carries a design to be applied tothe base, or the design itself, which is then covered by a support film,which thus constitutes a covercoat as well as a support for the designafter its release from the paper backing and before firing of the basedecorated therewith. The design, which may be applied to the transferpaper in -any suitable manner, such as by the silk-screen printingmethod, may consist of a ceramic color or vitrifiable enamel or of ametallic Lustre composition, such, for example, as lthat known as LiquidGold, which consists essentially of a solution of a sulpho-resinate ofgold in lsuitable solvents, or of a mixtu-re of the two materials.

Whilst either of the -above two kinds of decalcomania may be employedfor the application of vitrifiable enamel decorations, it has been foundthat the successful application of decorations in gold cannot beachieved with decalcomanias in which the design is `applied over thesupport film, but that it is essential to employ decalcom-anias of thecovercoat type, that is to say those in which the support film overliesthe design.

The covercoat support film at present used on decalcornanias carryinggold designs is of a cellulosic nature and based on ethyl cellulose.Such a covercoat enables a bright gold ldecoration to -be obtained on aglass or pottery base after firing, but is unfortunately notsufficiently fiexible for ease of handling and, consequently, diicultyis often experienced in applying a design film to an article ofcomplicated shape such as is frequently produced in the potteryindustry.

On the other hand, covercoat-type decalcomanias, carrying designs inceramic color or vitrifiable enamel, usually employ resinous orresin-based covercoats, such, for example, as an acrylic resin, whichpossesses the physical characteristics, such as Iflexibility, requiredfor ease of application to complicated shapes and is consequently muchto be prefer-red to cellulose-based materials.

Whilst resin-based covercoat decalcomanias have proved eminentlysuitable for use for applying ceramic colors, attempts to use suchcovercoats with gold-designcarrying decalcomanias have met with littleor no success, mainly owing to the fact .that reaction occurs betweenthe lgold `design film and the covercoat which destroys not only thebrightness of the fired gold film, but also its adherence to the base.It appears, moreover, that the usual solvents employed in the covercoatsolution tend to dissolve the gold film and separate the 4resinousmaterial in the gold composition.

The principal object of this invention is to overcome the abovedisadvantage in the use of resin-based coverlCe coats and to enable suchcovercoats to be successfully used with decalcomanias carrying a design:in gold.

Another object is to provide an improved gold-carrying decalcomania foruse in the decoration of heat-resisting bases.

A further object of the invention is to provide an -improved method ofdecorating a heat-resisting base with designs in gold.

With these and other objects in view, the invention provides adecalcomania or transfer of the c-overcoat support film type in whichthe design is applied to -a paper backing beneath the support filmWhichconstitutes the covercoat, which comprises a design layer formedof, or comprising a gold-containing composition, a covercoat supportfilm formed of a resin-based material, and, between the `design layerand the covercoat film, a protective layer of an oxidizable orpolymerizable material which is impervious to the covercoat material andis inert to the gold in the design layer.

By this means the `disadvantages -hitherto associated with resin-basedcovercoats on gold-design-carrying decalcomanias are entirely obviatedyas the intermediate protective layer prevents penetration of anysolvents from the covercoat film to the gold design and also preventsany reaction -between the resin in -the covercoat and the gold in thedesign layer during firing of the design on the base.

The invention also comprises a method of making a decalcomania ortransfer of the covercoat support film type including the steps ofapplying 'a gold-containing design layer to a paper backing, applying,to the said layer, an intermediate protective layer of an oxidizable orpolymerizable material which is inert to the gold in the design laye-rand then -applying to said intermediate layer a covercoat support filmformed of a resin-based -material, said intermedate layer also beingimpervious to said covercoat material.

The intermediate protective layer may consist of :an alkyd resin, aphenolic resin, or a urea resin.

The covercoat support film may consist of any known resin-basedcovercoat solution at present used with cer-amic color or enameldecalcomanias, such, for example, as a methyl methacrylate resin-basedfilm.

In carrying out the invention in practice, the intermediatepolymerizable protective layer may advantageously have the followingcomposition, namely,

Percent Short oil alkyl resin (60% non-volatile in xylol) 25.00

Cellulose nitrate 6.25 Plasticizer 6.25 High boiling solvent 62.50

A suitable covercoat support film may have the following composition:

The gold-containing design layer used may be any known and commerciallyavailable Liquid Gold preparation. The composition of such materialsforms no part of this invention, and it will sufiice to Say that ingeneral they are composed of -a sulpho-resinate of gold in suitablesolvents, usually with the addition of the resinates of other metals.The design layer may consist solely of a gold preparation, or of amixture of such a preparation and one or more ceramic colors orvitrifiable enamels, -according to the requirements of the final desireddecoration.

The invention is illustrated, by way of example, in the accompanyingdiagrammatic drawing, the single figure of which represents a sectionthrough a transfer or decalcomania embodying the invention.

In the drawing, 1 represents a gummed paper backing, the adhesive layerbeing represented at 1a; 2 a design film or layer formed of a LiquidGold preparation, 3 an alkyd resin protective layer of the abovespecified composition, and 4 a covercoat support lm also having thecomposition given above.

The layers 2, 3 and 4 are each preferably applied by the silk-screenprinting method, the gold design layer being applied through a plainweave mesh screen having 200 strands to the inch. A coarser mesh screenhaving 90 strands to the inch is preferably used for applying the thecomposition given above.

Whilst in the above one example of the invention has been described, itis to be understood that the invention is in no way limited to, or by,this example, but that modications may be made thereto without departingfrom the scope of the invention. For example, any other suitable LiquidGold design preparation may be used, and linseed oil or tung oil oranother polymerizable resin other than an alkyd resin may be employed.Again, the covercoat may have a different composition from that givenabove. Furthermore, the constituent layers of the decalcomania need notbe applied by the silk-screen printing method but any other suitablemethod, such as spraying or painting may be used instead.

It is, moreover, to be understood that the invention is intended toinclude within its scope a method of decorating a heat-resisting basewith a design or decoration in gold with the use of decalcomania inaccordance with,

or when made by the method of, the invention and any heat-resisting basewhen so decorated.

What we claim is:

1. A water release transfer of the covercoat support film kindcomprising a paper backing carrying a layer of a water-soluble adhesive,a design layer comprising a sulfo-resinate of gold on the said layer ofwater-soluble adhesive, a protective layer comprising a materialselected from the group consisting of alkyd resins, phenolic resins, andurea resins covering said design layer and a flexible covercoat lmformed of resin-based material covering the said protective layerincluding the edges of said protective layer and the edges of saiddesign layer, the protective layer being impervious to the covercoatfilm and inert to the gold in the design layer.

References Cited UNITED STATES PATENTS 1,634,617 7/1927 Hart 156-2401,658,263 2/1928 Stanley 40-21 1,888,154 11/1932 Allen et al. 117-3.32,017,367 10/1935 Kurz 117-3.3 2,124,232 7/1938 Kittredge et al. 117-1222,970,076 1/ 1961 Porth 156-89 3,156,580 11/1964 Howard 117-75 FOREIGNPATENTS 784,966 10/ 1957 Great Britain.

EARL M. BERGERT, Primary Examiner.

H. F. EPSTEIN, Assistant Examiner.

1. A WATER RELEASE TRANSFER OF THE COVERCOAT SUPPORT FILM KINDCOMPRISING A PAPER BACKING CARRYING A LAYER OF A WATER-SOLUBLE ADHESIVE,A DESIGN LAYER COMPRISING A SULFO-RESINATE OF GOLD ON THE SAID LAYER OFWATER-SOLUBLE ADHESIVE, A PROTECTIVE LAYER COMPRISING A MATERIALSELECTED FROM THE GROUP CONSISTING OF ALKYD RESINS, PHENOTIC RESINS, ANDUREA RESINS COVERING SAID DESIGN LAYER AND A FLEXIBLE COVERCOAT FILMFORMED OF RESIN-BASED MATERIAL COVERING THE SAID PROTECTIVE LAYERINCLUDING THE EDGES OF SAID PROTECTIVE LAYER AND THE EDGES OF SAIDDESIGN LAYER, THE PROTECTIVE LAYER BEING IMPERVIOUS TO THE COVERCOATFILM AND INERT TO THE GOLD IN THE DESIGN LAYER.